Deep well pump



Nov. I 1

5 932 B. H. scoTT DEEP WELL PUMP Filed Feb. 4, 1930 4 Sheets-Sheet l/f/s: //A

NOV. 15, B H SCOTT DEEP wELL PUMP Filed Feb. 4, 1930 4 sheets-Sheet 2NOV- B. H. sco-r1- DEEP WELL PUMP Filed Feb. 4, 1930 4 Sheets-Sheet 3NOV. 15, 1932. B H SCOTT 1,887,736

DEEP WELL PUMP Filed Feb. 4. 1930v 4 sheets-sheet 4- Patented Nov. 15,19,32

UNITED STATES PATENT OFFICE BERNARD E. SCOTT, O GLENDALE, CALIFORNIA,ASSIGNOR TO BODLESS :PUMP COMPANY, F LOS ANGELES, CALIFORNIA, ACORPORATION OF NEVADA DEEP WELL PUMP Application led February 4, 1980.Serial No. 425,799.

This invention relates to deep well pumps and an object, in general, isto improve the construction and operation of this class of pumps.

More particularly, the invention relates to that type of pump that isoperated by a motor means which, in this instance, is of the fluidpressure operated type.

l Another important object is to eiect a continuous ilow of liquid fromthe well so as to minimize any tendency to sanding-up of the pump and soas to minimize power reuirements in operating the pump, since t ere isno inertia of a stationary column of 35 liquid to overcome during thepumping cycle.

Another object is the evenness of power requirements in operating thepump throughout the pumping cycle.

Another object is ease with which the pump may be freed from cloggingsand in event of the pump not being operated for a period of time andthus permitting sand to settle in the pump so as to cause what iscommonly termed sanding-up.

Another important object is to provide a construction that will utilizetubular members of standard dimensions so that many parts of the pumpcan be manufactured from cold rolled members produced by manufac- Yturers thereof and carried in stock for many uses.

Other objects and advantages will appear in the subjoined detaileddescription.

The accompanying drawings illustrate the invention:

- Figure 1 is an elevation, partly in section, -of a rodless pumpconstructed in accordance with the provisions of this invention. Thepump is shown as being shorter in proportion to its diameter than wouldbe customarily employed in practice, in order to contract the view.

Figures'2, 3, 4, 5, 6 and 7 are enlarged longitudinal sections ofdifferent portons of the pump shown in Fig. 1, the vviews taken insuccession representing diiferent successive portions from the upper endof the pump to the lower end.

5o Figures 8, 9 and 10 are horizontal sections on the lines indicated by8-8, 9-9 and 10-10, respectively, Fig. 2.

Figure 1l is a horizontal section on the line indicated by 11-11, Fig.5. y

Figures 12, 13 and 14 are horizontal sec- 55 tions on the linesindicated by`12-12, 13-13, 14--14, respectively, Fig. 6.

yFigure 15 is a horizontal section on the line indicated by lf3- 15,Fig. 7.

Figure 16 is a horizontal section on the c3 line indicated by 16-16,Fig. 4.

Figure 17 is a diagrammatic view illustrating the dierential pressureareas of the pump.

Referring to the drawings, the valved hollow or tubular plunger of thepum is indicated at 20, and the valved working arrel, in which saidplunger operates, at 21. It is to be understood that any suitable typeof valved working barrel and valved plunger may be employed, but thetype disclosed in the drawings and now to be described in detail, hasparticular advantages which will be mentioned hereinafter.

Into the lower end of the working barrel 214 is threaded a tubular valvebody 22 which is provided near its upper end with an internal annularbeveled seat 23 against which seats a valve closure 24 which, in thisinstance, is in the form of a plug. It will be noted that so the valve24 closes upwardly on the seat 23 and opens downwardly. Opening movementof the closure 24 is restricted by a stop 25 which, in this instance, isin the form of a bar or pin that extends across the bore of the body 22and has its opposite ends anchored in said body. In this instance theworking barrel is constructed in sections which are held assembled byreason of a lower section 26 being screw-threaded into -the lower end 9oof a. tubular jacket section 27 and the upper section 28 beingscrew-threaded into the upper end of said jacket section 27. The pump isclosed at its lower end by a hemispherical cap 29 which is screwed ontothe 95 lower end of the section 26.

The working barrel 21 is spaced from the jacket 27 to form an annularpassage 30 into which liquid may flow from the cap 29, through one ormore vertical passages 31 in 100 the section 26. The body 22 projectsbelow the lower end of the section 26 into the cap 29 and is providedwith one or more horizontally opening ports 32 so that the liquid canfreely flow into the interior of the cap 29 from the valve body Thevalve'body 22 and closure 24 together constitute the foot or standingvalve, and it will be noted that the construction of said valve permitsthe lower end of the plunger to a preach within a relative minuteydistance of) the seat 23 so that when the plunger descends practicallyall of the liquid in the working barrel b elow said plunger will beforced from said working barrel.

`.The plunger is provided at its lower end' with a valve seat 33 againstwhich closes a valve closure member 34 which, in this instance, is inthe form of a cone-shaped plug adapted to fit the seat. The closure 3 4is provided with a stem 35 which works in a guide 36. It will be notedthat the valve closure 34 closes upwardly onto its seat and opensdownwardly. Opening movement of the closure 34 is restricted by ashoulder 37 on the stem 35 coming into engagement with the upper face ofthe guide 36. Liquid enters the pump through one or more ports 38 in thebarrel section 28, said ports 38 preferably extending aslant downwardlyand inwardly so that any gas tending to escape between the workingbarrel and the plunger, on the down stroke of said plunger, will readilyflow through the ports 38 into the bodyof oil that is outside of thepump, so that said gas will not interfere with the operation of thepump.

A suitable operating means is provided for the plunger 20 and saidmeans.' in this iiistance, is in the form of a motor, indicated ingeneral by the character 39, and the motor, in this instance,is'operated by fluid pressure as, for example, by liquid that is forcedfrom the surface of the earth into the pump by another pump, not shown,at the surface.

Oil is a very suitable medium for operating the motor which isconstructed as .follows There is a cylinder 40 which, in this instance,is of sectional construction and the sections are held assembled byreason of the lower section 41 being screwed into an intermediatetubular member 42 and the upper section 46 being screwed into the upperend of said member 42. A tubular jacket 43 surrounds the tubular member42 and is spaced therefrom to form an annular passage 44.I The tubularmember 42 is spaced from the cylinder 40 topform an annular passage 45for liquid. The lower end of the passage 45 communicates with the boreof the pump barrel through a port or ports 451.

The lower end of the jacket section 43 is screwed onto the upper end ofthe barrel section 28 and the upper end of said jacket section 43 isscrewed onto a coupling 46 that connects the jacket section 43 to ajacket section 82.

The outside diameter of the barrel section 41 is less than the insidediameter of the jacket 43 so as to form an annular space 47 whichcommunicates the passage 44 with an annular passage 48 that existsbetween the jacket 43 and a tubular guide 49 for the stem 50 thatconnects the plunger with a motor piston 51. In this instance the steinguide 49 is of sectional construction and the sections are held tightlya ainst one another by reason of the upper gui e section engaging thelowei` cylinder section 41 and the lower guide section engaging theupper barrel section 28. The lower end of the passage 48 communicateswith the upper end of the passage 30 through a vertical port or ports481 in the barrel section 28. The ports 481 are staggered with respectto the ports 38 so as to avoid cutting into said ports 38. The stem 50comprises a relatively lon or tubular section 52, a member 53 screweinto the lower end. of the member 52, and a member 54 screwed into theupper end of said membei` 52. The lower end of the stem member 53terminates in a head 55 that is confined between internal shoulders 56,57 in the plunger. The diameter of the head is slightly less than theinside diameter of the plunger at that point so that self-alining of theplunger within the workin barrel can readily take place irrespective owhether or not the stem is alined with the plunger. In other words, thehead 55 and shoulders 56, 57 constitute a loose connection between theplunger and the stem so that the self-alining can take place. The head55 is flattened on its sides so as to permit liquid to How past saidhead within the plunger.

The stem member 54 connects with the piston 51 by reason of said member54 terminating at its upper end in a head 58 which is confined betweenshoulders 59 and 60 provided in the piston. The piston is provided witha chamber 6l in which is a coil spring 62 that surrounds a tubularspring guide 63 between a lower spring seat 64 and an upper spring seat65.

The spring seat 64 rests upon a hollow member 66 which forms theshoulder 59. spring seat is tubular and surrounds a stem section 67which is threaded into or otherwise secured at its lower end to thespring seat 64. Thus relative motion may take place between the springseats 64, 65 for compression and expansion of the spring. The springseat 65 is flattened on its sides to permit of the power fluid passingit.

The stem section 67, in this case a rod, is in telescopic relation withanother stem section 68 which, in this instance, is of tubularconstruction and is provided at intervals silbstantially throughout itslength with ports 69. Near its upper end the stem section 67 is providedwith an annular shoulder 7 0 adapted to engage an annular shoulder 71within the lower end of the stem section 68 when the piston moves to thelower end of the stroke so as to pull downwardly the stem section 68, tothus operate the ower fluid control valve 72 which is strewe on orotherwise secured to the u per end of said stem section 68.

The valve isv of the slide type and is provided in its periphery with anannular passage 73 adapted, when in its lower position, to communicateat its upper end with a port or ports 74 in a. valve body 75 providedwith a bore 76 in which the valve 72 slides. When in this position, thelower end of the passage 73 communicates with an' enlarged bore portion77 in the valve/body 75. When said valve is in its uppermost position,the upper end of the passage 73 registers with a port or ports 78extending horizontally in the valve body and, in thls up er position ofthe valve 72, said valve cuts olii communication between the passage 73and the cham-A ber 77, and the lower end of the passa 0d registers withthe orts 7 4.A The valve 75 is provided with 79 which communicate attheir lower ends with the chamber 77 and ast their upper ends with abore 80 of a coupling member 81 that is screwed into the upper end of ajacket section 82, the lower end of which 1s screwed onto the upper endof the cylinder section 46. The ports 79 are in staggered relation tothe ports 74, 78 so as to miss the latter mentioned ports. The couplingmember 81 is provided with a vertical port or ports 83 whlch communicateat their upper ends with an enlarged bore portion 84 of the couplingmember 81 and which communicate at their lower ends with an annula\r\passage 85, that exists between the valve body 75 and the jacket section82 and that communicates with the passage 88. f f

This extension 95 is spaced from the stem section 68 to form an annularpassage 96 with which the ports 69 communicate and the upper portion othe extension 95 is provided with ports 97 to permit of liquid flowingin and out of the cylinder above the piston on the down and up strokes,respectively, of said piston.

The piston is provided at its inner face with spaced, beveled, annularshoulders 98, 99, the upper shoulder 98 adapted, when the pistonascends, t'o force the detents 93 inwardly so as to engage the shoulder91, thus locking the valve stem against upward movement. On the downstroke of the piston the shoulder'99 is adapted to thrust the detents 93inwardly so as to engage the shoulder 92 to prevent downward movement ofthe valve 7 2. The shoulder 98 is near the up er end of the piston andshoulder 99 is be ow the middle of said piston and is formed by theupper end wall of an annular, internal recess 991 in the piston. It willbe noted that,

a vertical port or ports 7 when the iston is driven downwardly so thatthe shoul er 99 forces the detents 93 into locking position, saiddetents will be maintained in the locking positions bv the inner face ofthe iston until the shoulder 98 passes below the evel of the detents.The shoulder 98 is formed by the end wall of an internal, annular recess992 in the upper end of the piston, which recess permits the detents tomove outwardly to unlocking position.

The ports 78 communicate the passage 85 with the bore 76 of the valvebody 75.

The outer ends of the ports 74 communicate with an annular passage 86that exists between the valve body 75 and an upward extension 87 of thejacket coupling 46, into 'which said extension is screwed. The lowe'rend of the annular passage communicates through a vertical ort or ports88 in the coupling 46 with the annular passage 44. The lower end of theannular passage 86 communicates with the annular passage 45 through anannular passage 89 that exists bgtween the coupling 46 and the valvebody The valve stem section 68, in this instance, comprises members ofdifferent outside diameters, and a means is provided for locking thelower one of said members 90 in two different positions to the extension95, said locking means being releasable by movement of the iston.

T is locking means, in this instance, is constructed as follows: Themember 90 is provided with upper and lower external annular .beveledshoulders 91, 92. Adapted to selectively engage the shoulders 91, 92 isa ball detent` or detents 93 which are carried 1n openings 94 in thetubular downward extenslon 95 of the valve body 75 that constitutes theupper head for the cylinder.

Likewise, as the piston is driven upwardy the inner face of the pistonmaintains the etents 93 in locking position until the recess 991registers with the detents 93, whereupon said detents are free to moveoutwardly into unlocking position. The spacing of the shoulders 98, 99is suicient to permit of full stroke of the piston.

The member 90 is provided with one or more ports 100 to permit of influxand efflux of liquid beneath the piston when the piston moves up anddown, respectively. The stem section 90 is provided near its lower endwith a shoulder 101 adapted to engage an abutment 102 formed, in thisinstance, by the lower end of the extension 95 so as to limit upwardmovement of the valve 72. Said shoulder 101 is in engagement with theabutment 102 when the shoulder 92 is in register with the detents 93.`Downward movement of the valves 72 is limited by an external, annularshoulder 103 on the stem section 90 enaging an internal, annularabutment 104 on e extension 95. The shoulder 103 engages .engaged by aninternal, annular shoulder 106 of the piston, when the piston descends,to effect compression of the spring 62 after the shoulders 7 0, 71engage.

In this instance, the pump barrel section .'41 comprises three tubularmembers, an outer member 107 which is screwed into the lower lmember109.

end of the member 42, a member 108`which is screwed into the member 107,and a member 109 that is screwed into the member 108.

The member 107 and, for a distance, the

member 108, are spaced Jfrom a portion of the member 109 to form anannular passage 110 which communicates the lower end of the cylinderbore with a vertical duct 111 in the The lower end of the duct 111communicates with a valve chamber 112 provided with a ball check valve113 that closes downwardly onto a seat 114 at the upper end of a port115 that communicates at its lower end with the passage 48.

The bore portion 84 of the coupling member 81 is threaded at 116 so thattubing can be readily connected with said coupling member though it isto be understood that, .by suitably packing the space between the pumpjacket and the well casing, not shown, the casing itself may be utilizedfor conducting the pumped fluid out of the well, in ,which event thetubing will not be employed.

The reduced bore portion 117 of the coupling member 81 is threaded forconnection with .pump tubing or with macaroni,

`which is the term ordinarily employed for designating the small tubingused, insome instances, for conducting the power fluid to the pump fromthe surface of the earth. The coupling member 81 is provided with 'avalve seat 118 on which is adapted to close a ball valve 119 toordinarily prevent the power fluid entering the bore of the valve body75.

From theforegoing, it will be seen that the cylinder and pump barrelare. connected together, with the pump barrel lowermost and that outsidethereof and concentric therewith is a jacket and that between the jacket'and the cylinder and concentric therewith and spaced therefrom, is the,tubular member 42 so as to form an annular passageway, the upper portionof whi ch lies between the member 42 and the jacket, the intermediateportion between the stem guide 49 and the jacket, and the lower portionbetween the pump barrel and the ]acket and, furthermore. it is seen thatthe stem of the valve 72 comprises sections in shift'ahle relation toone another, the one connected with the valve 72 and the other adaptedto be engaged by the piston on its up stroke to compress the spring, andthat said stem sections are provided with the' shoulders 70, 71 adaptedto engage on the down stroke of the plston to compress the spring.

The invention above described operates as follows: In the ordinaryoperation of the pump, the fluid under pressure, as for eX- ample, cleanoil, will be forced down the macaroni, or other tubing, 120 and, assuminthat the valve 72 is in its upper position an is locked in said positionby reason of the detents 93 engaging the shoulder 92, the power fluidwill flow through the ports 79 into the chamber 77 and past the lowerend of the valve 72 into the upper end of the passage 96 and through theports 69 into the bore of the upper stem section 68 and through theports 97, thus moving said piston on its down stroke. As the pistonstarts down, the shoulder 99 forces the detents 93 inwardly into lockingposition 'against the shoulder 92, thus to prevent the valve 72 fromdropping after the piston has descended a sufficient distance to permitof full expansion of the spring 62. The oil or other liquid beingpumped, while the piston moves downwardly, will enter the ports 38 fromthe well and flow into the hollow lunger. At initiation ofthe downstroke o the plunger, by downward movement of the piston, the valve 34will be closed by differential pressure, thus forcing the oil beneaththe plunger Within the lower portion or suction chamber of the pumpbarrel past the valve closure 24, thence through the ports 32 into thecap 29, thence upwardly through the ports 31 into the passage 30, thencethrough the ports 481 into the passage 48, thence through the passage 47into the passage 44, Iand thenceinto the passage 85.

During the down stroke of the piston and plunger, the power fluid thatis within the cylinder below the lower end of the piston will be forcedthrough the ports 451 into the passage 45 and will pass upwardly throughsaid passage, thence through the passage 89, thence through Athe passage86, thence through the ports 74 into the valve passage 73, and thencethrough the ports 78 into the v passage 85, where it mixes with thepumped fluid that has entered said passage from the ports 88. The mixedpumped and power fluids will then flow upwardly through the ports 83into the larger bore portion of the coupling member 84, thence upwardlythrough the pump tubing 121, if such tubing is employed for thispurpose, or otherwise, upwardly through the well casing to the surfaceof the earth.

When the lower end of the piston reaches a point Iabout three inchesabove the lower end of the cylinder, the shoulders 70, 71 will engage,thus holding the lower spring seat stationary. Then the shoulders 105,106 engage upon further downward motion of the piston, thus compressingthe sprlng 62 between the spring seats 64, 65. After the spring has beencompressed, further downward movement of the piston will bring theshoulder 92 opposite the recess 992, whereupon the shoulder 92 willthrust the detents 93 outwardly and thus permit the spring 62 to morethe valve 72 into its lower position, thus shutting off the power fiuidfrom the passage 96, whereupon the piston and plunger come to rest.

The valve 72 now being in the position shown in the drawings, the powerfluid passes from the chamber 77 through the passage 73, thence throughthe ports 74 into the passage 86, thence through the passage 89, andthence through the passage 45, thence throu h the ports 451 into thelower end of the cy inder so as to roduce upward pressure on the lowerend of t e iston which, accordingly, is driven upwar ly, carrying withit the pump plunger. As the plunger ascends it tends to produce apartial vacuum within the pump barrel below the valve 34, thus closingthe valve 24 and opening the valve 34, thereby admitting to the pumpbarrel below the valve 34 the oil that has entered the plunger throughthe ports 38. As the piston ascends, the power fluid above the pistonwill be forced through the ort-s 97 into the passage 96, thence throughthe ports 69 into the stem of the valve and, also, through the ports 100into the hollow stem. From the stem the fluid asses through some of theports 69 into tiie passage 96 and from said passage 96 back into thestem through other of the ports 69; thence through the valve 72 into theupper bore portion of the valve body 75, thence laterally through theports 78 into the passage 85, thence through the ports 83 and on out ofthe well through the ump tubing or casing, as the case may be. s thepiston ascends, when it reaches within, for example, three inches of theupper end of its stroke, the spring seat 65 engages the lower end of thestem section 68, thereby compressing the spring 62.

After compression of the spring, further upward movement of the pistonwill bring the piston recess 991 to register with the shoulder 91 and,accordingly, the expansive force of the spring will move the valve stemupwardly until the shoulder 92 is alined with the detents 93, the valve72 in this upper position shutting off the power fiuid from the ports 74and this completes one cycle of the pump. The cycle will then berepeated as long as the power fluid is supplied to the Shrduld the pump,for any reason, be permitted to stop its operation and, in such event,should packing of the sand within the pump prevent starting of the pump,by supplying the power fluid in the manner hereinbefore described, thepower fluid will be supplied to the pump in a reverse direction, that isto say,

113 into the valve chamber 112, thence through the port 111, thencethrough the passage 110 into the bore ofthe cylinder beneath the piston,thus tending to drive the piston upwardly if it is not at the upper endof its stroke.

While the piston is moving upward the flow of the power fluid thereaboveis in a reverse direction to that which it has for causin down stroke ofthe piston, as in the norma operation of the'pump as described above. Ifthe pump mechanism fails to respond quickly, when the power fluid isthus supplied in a reverse direction, the direction of the power fluidwill again be reversed by supplying it to the tubing 120 and thisalternate method of supplying the operating fluid will be repeated asoften as necessary to loosen the packed sand or mud in the pumpsuflicient to permit normal operation of the pump, as hereinheforedescribed. Cleansing of the pump in this manner results because even ashort reciprocat-ory movement of the piston will permit of sufficientmovement of the fluid to take place to effect washing of the sand or mudout of the pumping mechanism.

The producing assembly, or, in other words, the pump barrel with itsfoot valve and the plunger with its valve, differs in every respect fromthe conventional types of well suction pumps operatedby sucker rods, asis the prevalent practice in the oil fields. In the conventional pumpthe plunger is provided with a discharge traveling valve positioned ateither the upper or lower end thereof and at the lower end of the pumpbarrel is a standing valve. As the sucker rods are drawn upward toelevate the plunger, the fluid is displaced above said plunger, causingthe puppped fiuid to flow out at the mouth of the we As the plungermoves upwardly, that portion of the barrel below the plunger becomes alow pressure chamber which receives a charge of fluid from the wellthrough the standing valve. Since all oil produced from oil wellscontains a quantity of gas which vaporizes under a decreased pressure,or agitation, the suction chamber of the old type of oil well pump,generally, is not entirely filled with oil but contains gas as well, thepressure of which varies directly with the pressure of the hydrostatichead in the well casing, since the rock pressure is the force that fillsthe suction chamber. As the plunger moves downward, the standing valvecloses and the gas in the suction chamber is compressed by Cil theweight of the sucker rod string, until pressure of the fluid in thesuction chamber is slightly greater than the pressure of the oil in thepump tubing that carries the pumped oil to the surface. When suchpressure is reached in the suction chamber, the traveling valve opensandthe downwardly moving plunger displaces the gas and oil upwardly.When the plunger again starts up, the traveling valve closes downwardand the compressed fluid from the suction chamber is then a part of thefluid column in the pump tubing above the plunger. This compression ofthe gasified fluid in the suction chamber at each down stroke of theplunger, represents an appreciable loss in the capacity of the pump andin the power that operates said pump.

Another major loss that occurs in such sucker rod operated pumps atpresent in use,

is due to what is generally known as gaslocking, the suction chamber.Various types of oil and gas separators or gas anchors are employed withthe pumps in an effort to cornbat this objectionable condition. Thefunction of -the gas anchor is to separate the free gas from the oilbefore the oil enters the suc-v tion chamber of the pump. Theperformance of the gas anchor is quite satisfactory insofar as itsaction on free gas is concerned, but the gas anchor, being attached tothe lower end of the pump and, accordingly, subjected to the pressureexisting in the well, cannot rid the pump of that gas which separatesfrom the oil after entering the suction chamber under lowered pressure'conditions within said chamber, or that gas which is freed from the oilthrough agitation.

Assuming, for example, that in the old type of ump there is a clearanceof .O02 of aninch tween the plunger and the pump barrel, on the upstroke, the oil seal between the plunger and pump barrel must withstandthe hydrostatic pressure of the entire column of fluid being lifted bythe plunger through the pump tubing, which pressure, for example, in awell having a depth of 5,000 feet, reaches approximately 2,000 poundsper square inch.

The oil in the clearance space serves as an impervious seal and alubricant for the upward moving plunger, provided that the agitativemovement of the plunger does not release any gas within the oil thatforms the seal. However, release of the gas from the seal usuallyresults, and as the gas is released, the pressure above the plungerprevents upward movement of the gas and, accordingly, the gas in theseal Hows downwardly as the plunger moves upward, resulting in thesuction chamber receiving a volume of high pressure gas which tends tohold the standing valve closed, thus effecting what is commonly known asa gas-lock. This gaslock cannot occur when using the hereinbeforeemptied of the from the working barrel through the stand ing valve bythe pressure applied downwardly by the plunger and, said standing valve,while the plunger is on its up stroke, is retained in a closed positionby the hydrostatic,

head of the fluid in the well, which hydrostatic head is against .theunderface of the standing valve. Accordingly, on the up stroke of theplunger', there 1s a low pressure area existing in the suction chamberbelow the plun er which causes the fluid from the well to ow downwardlythrough the orts 38, through the plunger and out throug the travelingvalve 34 into the suction chamber.

If it be assumed that the hereinbefore described valved pump barrel andvalved plunger of this invention are installed in a well at a depth of5,000 feet witha plunger clearance of .002 of an inch, the plunger beingdown, the power fluid is applied to the under side of the piston, thusdriving the plunger on its up stroke. This causes a low pressure area toexist in the suction chamber between the plunger and the closed standinvalve. Accordingly, there will be a llow o oil through the ports 38,into the plunger and past the valve 34 into the suction chamber. Anyfree gas contained in the suction chamber seeks, naturally, the upperend of the chamber immediately under the plunger and, as additionalpressure is produced on said gas by the next downward movement of theplunger, any slippage of fluid that might occur between the plunger andthe working barrel would result in flow of said fluid from said suctionchamber, past the plunger, and upwardly and out through the ports 38into the well casing. When the plunger reaches the lower end of its downstroke, it will be noted that the lower end of said lunger can approach,approximately, withln gg of an inch of the standing valve so that thesuction chamber is (practically fluid being pumpe and there is no deadspace for the accumulation of high pressure gas as results in the olderforms of pump which employ a standlng valve that works within a cage.

There is thus avoided any resistance to inflow of the liquid to thesuction chamber on the suction stroke of the pump, due to compressed gasas occurs in the older types of pump. In the older type of pumpmentioned above, the valve cage occupies from four to ei ht inches ofspace within the suetion channer of the pump, thus permitting gas to becompressed by the plunger within said space. This compressed gasexercises pressure on the standing valve ball until the plunger hasascended to a point that permits of reduction of the gas pressuresufficient to permit the standingvalve to open. Thus, the

standing valve is closed during a large part of the upward suctionstroke of the plunger and this, of course, lowers the operatingelliciency of the pump. This condition is generally known as a partialgas-lock and it cannot exist in the pump hereinbefore described.

With the construction hereinbefore described, it is possible to employsuch ratios of pressure faces for the piston and plunger as will producea substantially balanced condition, whereby the ressure required on theup and down stro es is substantially the same, and this pump, althoughprovided with but one suction chamber, is double actin nsofar as thereis always a flow of fluid rom the pump.

The balancing effect is produced by exhausting the power fluid beneaththe piston into the column of fluid forced from the suction chamber onthe down stroke of the pump and by exhausting the power fluid into saidcolumn of fluid from above the piston on the up stroke of the piston.The lower faceof the piston has less area than the upper face,

due to the presence of the connecting stem- The ratio pf piston andplunger pressure faces, at present employed, is as follows: Referring toFig. 17, the upper face of the piston has a diameter of 2.25 inches andan area of 3.976 inches; the lower face of the piston is of the samediameter as the upper face, but the connecting stem has a diameter of1.1417 inches and an area of 1.0246 inches, thus leaving an effectivearea of 2.9515 inches for the lower face of the piston. The upper faceof the plunger is not a factor in the ratio. The lower face of theplunger has a diameter of 1.75 inches and an area of 2.4053 inches.

Thus, on the down stroke the ratio of the surface against which powerfluid is acting to the surface against which the pressure of the exhaustfluid is exertedequals:

Area of upper face of power piston been described more particularly asoperating in an oil well, it is to be understood that an other fluidthan oil may be advantageous y pumped. If, for example, water is to bepumped, the power fluid may be water or air under pressure. Whatever thecharacter of the power fluid'employed, the pressure thereof 1s producedby a suitable pump or compressor at the surface of the earth or gas froma gas well maybe employed at its natural discharge pressure from said1vlvell if such discharge pressure is sufficiently claim:

1. A rodless well pump including, a working barrel, a standing 'valvefor the working barrel, a hollow plunger in the barrel, a valve for theplunger, a means to carry the pumped liquid upwardly from the workingbarrel, a cylinder, a piston in the cylinder connected with the plun er,means providing passages for the flow o an operating'fluid to thecylinder and the flow of said operating fluid from the cylinder into theliquid column being pumped, a valve to control said passages, a soringmeans tensioned by movements of t e piston as it nears the opposite endsof its stroke to move lthe valve in opposite directions, and a meansreleasable by urther movement of the piston toward said opposite ends topositively lock the valve in di erent positions against movement by thespring means while tensioning of the spring means 1s occurring.

2. A rodless well pump including a cyl` inder, a piston in the cylinder,a valved working` barrel connected with the cylinder, a valved hollowplunger in the work' ng barrel connected with the piston, a meansproviding a passage for fluid from the working barrel past the cylinder,and a means to alternately apply fluid pressure to the opposed pressurefaces of the piston and to alternately exhaust the pressure fluid fromopposite ends of the cylinder into said passage, the ratio of the areaof one pressure face of said piston to the Arca of lower face of powerpiston lower face of production plunger 2.9515 2.4053 :'74

On the up stroke the ratio of the surface against which power fluid isacting to the sum of the areas of the other pressure face of said pistonand of the pumping pressure face of the plunger and its valve beingapproximately the same as the ratio of the area of said other pressureface of the piston to the`\fiist mentioned area.

,3W A lifpdless well pump including a cylinder, ampiston' in thecylinder, a'working barrel connected with the cylinder, a downwardlyopening standing valve for the working barrel, a plunger in the workingbarrel connected with the piston, a' downwardly opening valve for theplunger, a means providing a passage for fluid from the lower end of theworking barrel past the cylinder, and a means to alternately apply tolfluid pressure to the o posed pressure faces of the piston and to aternately exhaust the pressure fluid from opposite ends of the cylinderinto said passage, the ratio of the area of one of said pressure facesto the sum of the areas of the other of said pressure faces and of thepumping pressure face of the plunger and its valve being approximatelythe same as the ratio of the area, of said other pressure face of thepiston to the first mentioned area.

Signed at Los Angeles, California, this 27th day of Januar 1930.

BE NARD H. SCOTT.

